This invention relates to H.sub.2 -receptor antagonist ascorbates derived from the lactone form of 3-ketohexuronic acid of Formula I: ##STR2## where (X) may be 1, 2 or 3 and (Y) may be 1 or 2, R.sub.1 and R.sub.2 are both hydrogen or R.sub.1 may be hydroxyl, R.sub.2 hydrogen or the O-alkylidene, 5,6-diacyl, 6-acyl derivatives thereof having two to sixteen carbon atoms, or a 6-phosphate, R.sub.3 being an organic base or a salt thereof having one or more basic functional groups, having H.sub.2 -receptor antagonist properties and capable of reacting with nitrous acid.
The invention also relates to a process for the preparation of the above described compounds.
In the process a 3-ketohexuronic acid, or derivatives thereof, of the Formula II: ##STR3## where R.sub.1 and R.sub.2 are as hereinbefore defined, is reacted at a temperature from 0.degree. C. to 60.degree. C. with an organic base or a salt thereof represented by R.sub.3 as hereinbefore defined, to give a compound of Formula I.